Volume 109, Number 6, March 2015
|Number of page(s)||6|
|Section||Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics|
|Published online||25 May 2015|
Relaxation processes after instantaneous shear-rate reversal in a dense granular flow
1 Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile - Santiago, Chile
2 Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad de Antofagasta - Antofagasta, Chile
3 École Supérieure de Physique et de Chimie Industrielles (ESPCI) - Paris, France
Received: 1 February 2015
Accepted: 20 March 2015
A numerical model of granular material at different packing fractions and under steady shear is submitted to a sudden shear reversal. We monitor consequences of the strong density and shear rate spatio-temporal heterogeneities, on the constitutive relations. We show that the dynamics can be decomposed into two subsequent regimes spanning a time scale inversely proportional to the shear rate. In the first regime, the non-local constitutive relation proposed by Bouzid et al. (Phys. Rev. Lett., 111 (2013) 238301) is satisfied hence accounting for the spatial heterogeneity of the fluidity parameter. However at later time, we find that the local constitutive relation can be applied, in spite of the fact that the fluidity parameter remains heterogeneous. This result opens a discussion on the significance of fluidity and hidden variables accounting for non-locality in a frictional packing of grains.
PACS: 47.57.Gc – Granular flow
© EPLA, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.